Case Studies

CL-500A Measures Effects of LED Street Lighting on Sleep Patterns

Can the color of street lights affect your sleep? This question required research by highly trained electrical engineers. CR Engineers of Fountain Hills, Arizona, set out to measure lighting color levels emitted by LED street lights in the City of Phoenix; in particular, the level of blue energy. CR Engineers is a consulting electrical engineering firm employing highly skilled individuals with hands-on technical backgrounds in various areas of electrical expertise. Their experience exceeds 1,000 projects ranging from low cost residential designs for local architects to large projects with construction costs over $25 million.

Light emitting diode (LED) lighting systems are used in a variety of ways, from consumer homes to street lights in major urban areas. The City of Phoenix received public concern regarding the LED street lights and how they were affecting resident sleep patterns. LED lights appear white but have a high level of short wavelength light or blue energy. Many confirmed studies have unequivocally linked ocular exposure to blue rich light to decreased serum blood levels of melatonin and corresponding negative effects upon sleep cycles. Luminous intensities and spectral content components directly correlate with melatonin suppression. CR Engineers set out to get answers.